- From: Ojan Vafai <ojan@chromium.org>
- Date: Tue, 10 Jan 2012 16:51:09 -0800
On Tue, Jan 10, 2012 at 2:38 PM, Adam Barth <w3c at adambarth.com> wrote: > On Tue, Jan 10, 2012 at 2:35 PM, Ian Hickson <ian at hixie.ch> wrote: > > On Tue, 14 Jun 2011, Adam Barth wrote: > >> On Tue, Jun 14, 2011 at 2:03 PM, Alexey Proskuryakov <ap at webkit.org> > >> wrote: > >> > 28.02.2011, ? 21:38, Ojan Vafai ???????(?): > >> >> FWIW, chromium is planning on experimenting with disallowing modal > >> >> dialogs during the beforeunload/unload events. > >> >> http://code.google.com/p/chromium/issues/detail?id=68780 > >> > > >> > What is the big difference between alerts from unload and alerts in > >> > general? Alerts are not particularly useful for anything besides > >> > debugging, and pagehide/unload handlers is a place where they I've > >> > found them particularly useful for debugging. > >> > > >> > Do we have at least anecdotal evidence that many sites are showing > >> > alerts from unload? When I'm seeing a site that tries to prevent me > >> > from leaving it, it's always by returning a string from > >> > onbeforeunload. > >> > >> I believe the motivation is to be able to close tabs quickly. If a tab > >> doesn't register for any unload / beforeunload events, the tab can be > >> kill instantly. If the site registers for unload but not beforeunload, > >> then, today, we need to wait for JavaScript to execute before closing > >> the tab. Without the ability to trigger alert and friends during > >> unload, we can hide the tab instantly and unload it in the background. > >> > >> We have lots of stats for how many tabs would benefit from this > >> optimization and how much time would be saved. It's surprisingly large. > > > > Any news on this? If Chrome was able to do this, it would be worth > putting > > in the spec to give cover to other browsers interested in the same > > potential performance improvement. > > Ojan probably has more concrete data. I think we got one or two > complaints, but no major problems. The only complaint I'm aware of is in http://crbug.com/97206. The bug comments are confusing. The primary issue there is WebKit not firing beforeunload/unload from frames in some cases, but there is one comment about code that calls "confirm" from unload handlers followed by a sync XHR to save data that now breaks. Ojan
Received on Tuesday, 10 January 2012 16:51:09 UTC